Signaling system for elevators



Dec. 25, 1928. 1,696,842

R. H. GAYLoRD SIGNALING SYSTEM FOR ELEVATORS Filed Aug. 22. 1923 2 Sheets-Sheet. 1

Dec. 25, 192s. 1,696,842

R. H. GAYLORD SIGNALING SYSTEM FOR ELEVATORS Filed Aug. 22, 1923 2 Sheets--SheetI 2 (E Fi q. 5. f i mi 34%*4'3 34 3s l l as 3l l bis lnven'cor:

Patented Dec. 25, i928.

' UN TED STATES ROBERT H. GAYLORD, OF LOS ANGELES, CALIFORNIA.

SIGNALING SYSTEM FOR ELEVATORS.

Application filed Aug-ust 22, 1923.

'.lhis invention relates to an improvement on a. type of elevatorsignaling system (liscloscd in the patent to James B. Smalley and Charles A. Reiners, No. 826,752, dated July 6 24, 1906, and one of the main objects ofthe present invention is to provide such an elevator signaling system with means for cont-rolling the floor or landing signals and car operators signals in such a manner that lo only one landingr signal and one operators signal will be displayed at any one time at or for a floor for a bank of elevators trave-lling in the same direction, thereby avoiding confusion to passengeis and operl5 ators which arises at the resent time from simultaneous display of signals for several elevators approaching the same landing,

A'further object of the invention 1s to provide means whereby the operator of a car 2U within the signal zone may'so control the signals that they will be transferable to the next following car to enter the zone, the completion` of said vsignal, transfer being accomplished when the aforesaid following 25 car enters within t-hev signal zone. This 'transfer of signals between elevators approaching a landing about the same time is very desirable where a large number of passengers are waiting at arlanding to be 3" served, as the operator of the'ca'r in. control of the signals can'itransfer the signals, thereby calling the passengers attention to the fact that another oar is also available to serve them.` jAn important object of the 1'.' invention istoprovide means whereby any elevator operator.(in case he is receiving a signal) `may advise himself whether or not another car is within the same signal zone, and govern his running accordingly.-

A still further object of the invention is to provide means whereby the operator inV any elevator car may so control -the signals as to permit him to take on passengers at a landingand on leaving the landing 45.alln\v the signals to remain in operative transferable condition so as to provide for operation under the control of a succeeding car.

Another abject of the invention is to 1"" apply in connection with the elevator signal system shown in the Smalley and Reiners patent aforesaid, an interlock such as de scribed in patent granted to me November 25, 1919, No. 1,322,895, so as to secure the advantages of such interlock in connection with the type of signal systemwhich is Serial No. 658,736.

shown in said Smalley and Reiners patent and which is now in general use.

An important feature of my invention is the introduction or addition to the landing and car signal circuits, of devices which will change or alter the current flow to the signals, and the responsive change thereby brought aboutbeing used for signaling purposes in the routine operation of -an elevator signal installation.

Another important feature of my inventionis an elevator signaling means whereby initial circuits are established to the signals f or the purpose of coacting in the operation of the signal controlling means, the signal controlling means in turn being under con- 'trol 'of interlocking means.

AThe accompanying drawings illustrate diagrammatically an apparatus suitable for carrying ont my invention:

Fig. 1 is adiagram of the circuit connections fortwo elevators.

' Fig 2,is assideelevation, partly in section ofan interlocking control. magnet. 80 Fig. '3is a plan viewfof said interlocking contrai device.

Fig; et is a side elevation of the signal setting and resetting device.` Fig. .5- is adiagram of the interlock control devices. Y f',

Fig. 6v is' Va longitudinal section of the car operated switch or commutator.

Fig. 7 vis a. section on line 7-7 in Fig` 6.

Fig, -8 is a section on line 8,-8 in Fier. 6.

Fig. 9 is a.- section o n line 9-9 in Fig. 7.

.1n Fig. 1 of the..,drawings I have illustrated dlagrammatically the contacts for the controlled switches -.or commutators for two v elevators. The construction and operation 9" of said switches is identical with the construction and operation. ,ofthe commutators shown and disclosed in saidySmalley and Reiners patent, the switches and commutators being, however, indicated in thediawing as adapted for a five story or fivc landing signal system in place of seven landings as shown in the Smalley and Reiners patent. In Fig. 1 therehas been omitted from the diagram most of thosev contact-plates which form no part of the electrical features in or der to simplify the same. In-this diagram l is a source of electricity-such, for example, as an ordinary dynamo. 2 and 3 are elevator cars which are adapted to travel up and down in their respective shaftsfand 4 is an electrically controlled signal carried by each car and which is preferably in the form of an electric lamp. Electrically controlled signals located along the elevator shaft may also he provided for signaling the intending passenger that a certain elevator car is approaching him in the direction which he desires to go. These signals are also preferably electric lamps and are indicated at 5 to 12, the top and bottom floors each being provided with a single lamp for each elevator, and each of the intermediate floors with :i pair of lamps for each elevator, such as 8 and 9 for the third floor. These will be usually located outside of the elevator shaft adjacent to each doorway, as is common at the. present time, one. of said lamps serving to indicate a downwardly moving car and the other one an upwardly moving car. There is also provided suit-able4 hand operated mechanism located at each floor, such as ordinary push buttons, by which the intending passenger may control part of any signal circuit, so that after he has pushed one of said buttons lie will close or cause to be closed a break in the said signal circuit, so that when the commutator closes the other break in sucli circuit the signal will be given. These push buttons o r circuit closers are in dica ted at 14 to 21, tw'oof :them being located at each floor, except the;top "and bottom floors, the upper ones, being ,to signal up wardly moving cars and the lower ones, being to signal downwardly moving cars. Each push button has a contact connected to one side of a battery 13 and a contact inem her connected to one of the settingmagnets hereinafter set forth, tho other side o f each settinfr magnets' beingconnected to the other side olf the battery 13. Two cars with lcorrespondingr floor sio'nals and commutatois are shown in Fig. 1,:but it' will be evident that the. system may be ada ted for any desired number of shafts,.and t altjtlie :same mayA be cross wired, so that one setof ushzbuttons will cont-rol the circuits ferial the ears of that bank, as in 'common in this art. It is not. thought necessaryto illustrate this duplication and cross connection `.in the drawings, as the saine will .be evidentto any person skilled in this art.' A car operated circuit controller, swtch or commutator is provided for each elevator shaft and is operated by connection with the corresponding car. The expression car operated in this con nection, nieansoperated Ain correspondence with 'the movement of the car; The commutator is adapted to determine the time when the signal shall be operated-that is, when the lights may be lighted up, providing that a push-button has been pushed to close the other normally openbreak in the signal circuit. Each car operated circuit controller or commutator consists of suitable fixed and relatively moving contacts and in the presA cnt embodiment thebrushes are indicated as constituting the moving members thereof` said brushes being arranged in two groups respectively corresponding to up and down travel of the car and adapted to contact ie spectively and alternatively with two grou ps of fixed contacts. Furthermore each said car operated circuit cont-roller or commutator comprises a moving member or brush carrier 22 (see Figs. 6 and 7) adapted to be moved back and forth by operation of thc corresponding car, said moving member, for example, comprising a nut 23, which is adapted to work on a screw shaft 24 operated by connection wit-h the car operating means, and suitable means are provided for tilting said moving member on said shaft t-o shift the brush carrier so that one group of brushes is operatively engaged with the corresponding Iixed contacts while the elevator car is'travelling upwardly and to shift the brush carryin means so as to cause the other group o brushes to operatively contactwith the other corresponding group of fixed contacts during the downwardl travel of the elevator car. The means for reversing the movement of the brush carrier may consist of a frictional bearing means as shown-at n Fig. 9, whereby the nut 23 is.caused to tendffovturn .one way or the other, in correspondencewith the reversal of motion of screw shaft 24, and a guide member 36 adapted to engage an arm 23 on mit 23 to hold thebriish carrier to one side while it is travelling n one direction, and to the other side while it is travelling the oppo-A site direction all as set forth in the patent to Smalley and leiners abovereferred to- The Circuit connections are also` controlled by mercury pots and restoring and setting niagnets, which have been shown in Fig. 1 adjacent the coinmutator to .more clearly indicate theirrelation; but they may be placed wherever convenient, and, in fact, are usually placed upon a separate support by themsclves,being suitably wired from each separate commutator ofthe bank of elevators, as indicated in Fig. 1.`

The group of fixed contacts for each ,down signal control, inthe commutator, comprises two series of contact plates; but they neednot necessarily be of the form shown in all cases. One suchfseries isV indicated at 25 to 2 7 and the other series at 28 to 30. These two series above indicated are for the car as it moves downwardly.`

as mercury pots 31 to 33 having pivoted contact arms 34) the connections includingT interlocking electromagnetic devices hereinafter described. Said pivoted arms 34 for 'mercury pots 31 to 33 are ope-rated by the setting vmagnets 38 to 40 controlled by the respcctive-"(lown push buttons 15, 17, etc., and said pivot-ed arms are all connected to one side of dynamo 1. Each setting magnet has an armature 41 (see Fig. 4) controlling the pivoted Contact arm The pivoted arm 34of each switch is normally out of contact with the mercury` and therefore causes a break in the signal circuit, and it. and the mercury pot constitute a switch. It will be obvious that there is no limitation to this form of switch, but this mercury pot. and pivoted lever construction is a cor.- venicnt one t-o use, as has been found by actual practice. The pivoted lever may be caused to drop into the pot by different mechanism; but it has been found that a magnet controlled by a floor push but-ton is a convenient and effective means to this end. In the present instance there is provided a setting magnet,such as 38 to 40 (see Fig. 4) connected to' a corresponding push but-ton, so thatl when a button, such as '15, is pushed it will close a 'circuit from batte'ry 13 through the corresponding setting magnet 38,thereby attracting its amature 41.and releasing the lever 34, which -Will drop into the pot, as indieatedin the diagram. There is also provided a restoring magnet, such as indicated at 431to 45,`'for each arm 34 for restoring the same vto the normal position shown in Fig. 4after the car starts to move away from the floor for 'which the signal has been given. This will be described more inidetail hereinafter. It will be observed from the above that each of the intermediate floors is served by one of said floor signals, such as 6, a. plate, such as 25, of one of said series connected therewith, and a plate, such as 28,' of the other series which is connected tothe source'of supply through a switch or other circuit closing or contactmeans, which is individually controlled as hereinafter described by an electromagnetic control device-included in a control circuit whiclris in` turn controlled by a hand operated mechanism, such as push button 15, located at said-floor at which the signal 6 is also located. In order to make electrical connection between plates'25 and 28, ctc., there. is provided a brush or brushes for each series of plates, these brushes, indicated at 47 and 48 being electrically connected as indicated. It willbe obviousl that when any one. pairof these brushes, 47 and 48, touch plates 25 and 2S, respectively, the floor lamp 6 will be lighted up, providing all other breaks in the circuit have previously been closed, as the third normally open break in the circuit (between plates 25 and 2S) will then be closed and this break will remain closed so long as any pair of brushes connects these plates. It is preferred to provide several pairs or these brushes as indicated at 47 and 48, and space thc pairs a distance apart less than the width of any single plate. of thrseries, so that the plates, 25 and 2.8, for c.\- ample, will be electrically connected whil'.- thc car is moving YFor several floors, so thai the floor light will light. up several .floors in advance of the car and remain lighted until the car reaches the floor, 'lhis relativiarrangementis shown in the diagram and will be referred to hcrcina ftcr when the part-icular construction of the brush carrier discussed hereinafter. It will be observed that the circuit from the dynamo passe-s through the car-light 4 and then to the long." contact strip 55, and there is provided a pair of brushes 56 and 57, connected as indicated, the brush 56 rubbing over strip 55 and the'brush 57 making contact with thc series 28 to 30. It is-preferred to provide the long strip 55 and the brush 56, rather than to attach the circuit from the car lamp directly to brush 57; but the construction shown .may not befnecessary in all cases. The car signal is therefore in circuit with a brushinithis instance brush 57-on the series of contacts 28 to 30. In the present embodiment this brush 57 is a separate brush from'any one of the brushes aforesaid, and thisfis the construction that'is preferred; but it will be observed (see Fig. l) that when these brushes'are in the position shown in vthat: figure the brush 57 rests upon the same plate as the brush 48, and at that time sail two brushes 57 and 50 are, in effect, a single brush. In order to light up the car light only a floor or so before the car reaches thi` floor, brushes l56 and 57 are located behind the brushes 47 'and 48, so that the floor light will be lighted up Abefore the car light lighted. There has also been provided another -pair of connected brushes, 5Gand 57, so that the car light may be lighted up slightly more than one floor away from the door. at which the car is to stop. Also there llas been provided a series of restoring mechanisms for automatically restoring thc circuits to normal condition after the car has passed by, in this instance raising the mercury pot arm out of the mercury. Such a series of restoring mechanisms is shown b v the restoring magnets 43 to 45, which are all the same as magnet 43 of Fig.` 4. lt will he observed that., for example, restoring magnet 43 (sec Fig. 4) when energized will raise the lever 34 and drop the right cnd of llusamc underneath the end of armature il. where it will beheld until the setting magnet 38 is again energized. In order to energia@ the restoringr magnets atthe proper time. there are 'provided a series of contacts 63 to 65 upon the connnutator and a brash tE- adapted to ride on said contacts and suitably connected to the battery 13, in this instance by being electrically connected to a brush 6T, rubbing over Contact strip 68,-50 that when Alulthe car starts to move away from the floor on which the signal has been given, brush 6G will engage contact 63, say, and energize magnet 43 to break the signal circuit at the mercury pot.

The brushes have been shown in Fig. 1 in the relative positions they occupy as the car is descending, these brushes controlling the signals to a down-moving car. The brushes for that part of the commutator corresponding to an upwardly moving car are shown in such position as to be inelfective in closing connection between the plates to on the up side, which are mounted in positions corresponding to the aforesaid plates 25 etc., on the down side, except, of course, in reverse order. When the car moves upwardly, the brushes for the up contact plates are shifted into a position by means operated by the car, as shown in said Smalley and Reiners patent, so as to make suitable connections for the control of the up signals, so as to operate the up signals and the signal in the car and the up restoring magnets. This shifting of the brushes will be referred to hereinafter., 86 to 88 representa set of setting magnets, and 90 to 92 a set of restoring magnetslfor the up side, these magnets being controlled in the same manner as above set forth. The .system is therefore provided with means for controlling the signals when the .car is moving up, substantially the same as those heretofore described for use when the car is moving down. 93 is a suitable resistance, and 94 is a. night signal or bell.

The above described construction and arrangement of the parts is substantially the same as described andillnstrated in the patent to Smalley and Reiners aforesaid, with the exception of the intercontrolling or interlocking means which are according to my present invention incorporated in the connections for the floor landing signalsin place of direct connection of the floor landmg signals to the mercury pots as set forth in said Smalley and Reiners patent. ySaid intercontrolling or interlocking means constituting the main feature ofthe present invention as applied to the control of the landing signals, is shown more fully in Figs. 2 and 3, each intercontrolling or interlocking means comprising a -plural-ity of controlling magnets 95, one for each elevator car or shaft, said magnets being mounted side by side so as to cooperate with an interlock which is common to all of them. Each magnet controls an armature 96 carrying or attached to a pivotal arm 97, which cooperates with a mercury pot 98 to control a shunt circuit as hereinafter described. Each armature or armature lever also cooperates with an interlocking member consisting for example of a. shaft 99 of insulating material mounted to turn in bearings 100 and having a notch 101 one face of which 102 is adapted to be engaged by the armature or armatnrrl lever so as to turn the interlocking memberT Said member tending to return to normal position under operation of a spring 103. Said notch in the interlocking members is f-:o formed that when said member is operated by any one armature lever in the manner (lescribed, the opposing face of the said notch will ass beneath the armature lever correspon ing to the other interlock magnet or magnets and prevent operation of same. The interlock magnet 95 is provided with two energizing coil portions which are connected in series relation and one of which 104 is of such high resistance that when both coils are in circuit the conductance of the circuit as a wholewill be insufficient to permit effective illumination of either the car signal or of the landing signal. 1V hen any interlock magnet operates its armature to close circuit at- 98, said high resistance winding is short circuited and resistance of the circuit as a whole is then sufficiently low to cause increased illumination of the signal at a landing which a ca r is approaching. In Fig. 2 the two windings are shown as distributed on a pair of magnet cores but in lF ig. 1 for simplicity only one member of the pair is shown. As my invention relates primarily to the interlocking feature, the complete circuit therefor will be traced as follows: from dynamo or source of current 1 through wires 105 and 106 to the series of pivotal arms 34, and from the mercury pots 31 etc., corresponding to said pivoted arms, a plurality of branch wires lead to the windings for the res ective interlock magnets for the down side o the commutator. The other end of said winding is connected by a corresponding branch wire 107 to a corresponding contact plate 28 etc., at the down side of the commutator. The opposing contacts 25 etc., for the down side of the commutator are connected by wires 108 to the down signals 6, 8, etc., at the floor landings, the other side of each signal being connected by return wire 109 to'the other side of dynamo 1. A connection 110 is made from the junction of the two windings aforesaid, to arm 97 so as to establish a `shunt connection including said pivoted arm 97 and the corresponding mercury pot 98. .so that when Said pivoted arm makes connection with said mercury pot the winding 10ft is short-circuited but the other winding 111 for magnet 95 is left in circuit. ,lt will be understood that there are as many sets of interlocking devices as therel are landing signals, including both up and down landing signals.

The wire 109 may be directly connected -to dynamo 1 but I prefer to include therein a normally closed switch indicated at 112, one side of which is connected by wire 113 to qui (he opposite side of the dynamo 1, and the othci side of said switch being connected to the return wire 109, and also to the car signal 4. From said signal a wire 114 leads to the long contacts 68 etc., aforesaid, in the correspondin r commutator so that the wire 113 to the dynamo from the switch operates as a common return for both the car signal circuit and the landing signal circuit and the switch is included in said common return so as to cut out both of said signa-l connections simultaneously.

115 is :1 normally closed transfer-button or switch in the car by which the operator may open the restoring magnet circuit and 'thus prevent the restoring magnet from opening the signal circuit at the mercury pot.

Asin the Smalley and Reiners systemv above referred to the landing signals for the top and bottom floors are connected by operation of the contacts on the commutator irrespective of any push button control. The pair of contacts 117, 118, on the commutator corresponding, for example, to the up sig nal at the bottom floor (that being the sole sivnal at that floor) are adapted to be conne .ted by the brushes 47 and 48 aforesaid, the contact 117 being.,connected to a landing signal, and contact 118 being connected to a switch means 119, controlled by an interlock magnet, asv above described for the intermediate landing-signalsso that only one landing signal can be displayed'at one time. Similar contacts and interlocking magnets are provided for the down signalat the top:

floor.

The operation isasfollows: l F-'1st condition-Assuming that push button 15 is closed, the correspondin setting magnet 38 is operated to close circuit at 3l. The first car to enter the signal zone for that floor will then cause circuit to be closed (by a pair of brushes 47- and 48) between contacts 25 and 28. Current will then llow from dynamo 1 through line 105 and 10G to :in arm 34, then to mercury pot 31 and the corresponding electro-magnet 95, and

thence by wire 119 to contact 28, thence.

through brushes 48 and 47, contact 25, a wire 108, lamp 6, wire 109,- switch 112, and wire 113 lm cl: to dynamo 1. This circuit includes the full resistance of magnets 95, and the initial current that momentarily flows at this time in the signal circuit is consequently insufiicientto effectively operate the landing signal lamp 6, but armature A96-being immediately operated, the arm 97 at once.

cuit will be established through its high reing-Z car.

sistance means, but the current will be insufficient to effectively light its landing signal lamp, the interlock preventing the armature from being drawn down to close the shunt circuit for the magnet coil through the mercury pot. When first car passes out of signal zone which means that. 47 and 48 pass olf `of segments 25 and 28, the corresponding magnet 95 is deenergized, said interlock releases and returns to normal, and immediatcly thereafter thc reset circuit is established and all circuits are restored ready for another push button operation. As soon as any car advances far enough into a signal zone tobi-ing the brush 57 into contact with the contact plate (for example 25) which is in connection with thc operators switch 34 and 31, a branch circuit is also closed from the contact, through brush 57, and 56, contact plate 55, wire 114, and car lamp 4, to switch 112, so that the car signal is effectively illuminated,unless another car is in control of that signal zone.A i. Each car is provided with two switches, one from the restoring circuit, and onefrom the common return of the signal operating circuits. If operator in advanced -car doesnt wish to lll) answer the signal he canopen bot-h switches -in which case the signal. is maintained for .and1moves on,.then as brushes 47 and 48 passoff of contacts v25 and 28, amature 96 is returned to normal :ande releases interlock so next following car picks up the signal, but the operator of first car. maintains his sig- .landing and operator knows another car is in the zone, and wishesthis following car to assist in taking on passengers'he may-open ,common line. switch, and his signals will go out, and following car signals come on thereby attracting passengers to this follow- These three switches (one automatic and two manual) can function singly or collectively to produce distinct results.

Assuming that an elevator enters a signal zone and the operator receives-,thev signal to stop, (say to take onpassengers) the operator can by opening his common line switch lll) immediately extinguish both the waiting passenger signal and his car signal, and if a following car travelling 1n the same dlrection is within the signal zone for that particular fioor or enters it while the switch is open, the signals will be transferred to this following car, this operator receiving his signal to stop and the waiting passenger will be informed that his car will be the next car to arrive at the landing. But one waiting passenger signal for one direction of travel will be in evidence at any floor, likewise but one car signal will be in operation, this eliminates a common cause of confusion both to the waiting passengers and operators, as in the systems now installed as many wait-ing passengers signals and operators signals are presented as there are cars within the signal zone (travellingr in the same direction).

An important advantage of this invention is that an operator may transfer the signals to a. following car, after receiving a signal and himself passing out of thc signal zone, this being done by the simple opening of his reset circuit switch. In this case the reset circuit switch and the car operated switch function together to transfer the signal to the next following car; It is evident that I have provided three separate switches which function differently when operated singly or collectivel under certain conditions and thus materia ly assist in more efficient elevator signaling. Another important advantage is the fact that any car in an installation may be operated inde cndent of the general system, with the entire elimination of false signals which are so confusing in systems now in operation` This feature lends itself particularly where any car in an installation is wanted' for express service.

A very im ortant advantage is that this system may Ilie incorporated with installations now in operation with very little changes or interruption of service. Of important value is the flexibility of the signal transferring feature whereby car relation positions do not control or govern the functioning of the signal' transfer.

Among the specific points of novelty in the above described system is the flexibility afl'orded in the general organization for the transferring andV control ofthe signals (in an interlocking elevator signal system), also the unmistakable presentation of the signals both to the waiting passengers and the operator without duplication or possibility of false signals. Moreover the signals relating to each elevator are directly controllable by the operator of that elevator. He may'at any time if within the signal zione extinguish all signals relating to his car, or lie may transfer a signal received to the next succeeding car, or he may reassume the signal for his own car provided a following car is not in position to receive the transfer of signals. Furthermore he may by momentarily opening and closing transfer' switch 112 advise, himself whether or not. another car is within the signal zone corresponding to the floor at which he has stopped or for which he has received a signal. If upon rc-closing this switch his signal does not reappear he will be advised that another car is within the zone and has assumed control of the signals for that floor.

It will be seen that as soon as a car enters a signal zone and is responding to a signal, an initial signal circuit is established for both landing and car signals but ineffective for signaling purposes, the effective potential atl the signal being insutiieient to effectively illuminate the signal, and that thc effectiveness of the signal circuit is dependent upon the interlocking means whether in a locking or normal position.

lVhat- I claim is:

1. An elevator signal system for a plurality of cars, comprising landing signals and car-operated switches corresponding to thc respective cars; control circuits including a source of current, circuit closers at the respective landings, and electromagnetic controlling devices; signal operating circuits including a source of current, contact means controlled by said'electromagnetic controlling devices so as to be operated under the control of the respective control circuits, contact means controlled by the corresponding car-operated switches, intercontrolling electromagnetic devices associated together according to floors and directions of travelof the cars, and corresponding landing signals, and each signal operating circuit initially including a resistance suf'licicnt to prevent effective operation of the corresponding landing signal; contact means controlled by said intercontrolling electromagnetic devices and adapted to short-circuit said resistance in any signal operating circuit upon energization of the corresponding 'intercontrolling electromagnetic device, so

as to permit effective operation of the. corresponding landing signal; and interlock means operated by said intel-controlling electro-magnetic' dev-ice,pand adapted upon operation' thereof by the intercom-rolling electromagneticdeviee corresponding to one car to prevent 'effective' operation of any of the other intercontrolling electromagnetic devices associated therewith.

V2. An elevator signal system as set forth in claim 1 and comprising inv addition a manually operatedtransfer switch ineluded in and adaptedto open eaclrsigual operating circuit so as to render the signals controlled thereby inoperative and to de-ener- Ygize the corresponding intercontrolling electromagnetic device and release the interlocking means operated thereby.

8. An elevator 'signal'isystem fora plurality of cars, comprising landing signals corresponding to the respective cars; a car operated'switch corresponding to each ear and having. contacts corresponding to the re `pett-ive landing signals and means operated in correspondence with the movement of the car t-o control circuit connection at such contacts; signal operating circuitsincludingr a source of current and thc respective landing signals and also including the. corresponding contacts of the car operated switches; control circuits including a source of current and circuit closers at the respective landings and also including electromagnetic means; circuit closers included in the respective signal operating circuit-s and operated by the respective electromagnetic means aforesaid to closc the respective signal circuits; each signal operatingr circuit also including an electromagnet of sufficient resistance to prevent operation of the signal,

and also including a switch con .rolled byv said electromagnet and connections including said switclpand a' part of said electromagnct and adapted to short circuit said part of the electromagnet to reduce thc rcsistance of the circuit upon operation of thc electromagnet, so as to cause increased current to flow in the corresponding signal circuit, and an interlocking member adapted to cooperate with the said eleetromag netically operated switches for each floor and direction of travel of the car, to prevent operation of any of said switches while any other of said switches for thatloor and direction of travel is in operation.

4. A system as set forth in claim 3and comprising in addition a manually operated switch in each car, adapted to oplen the signal o ratin circuits corresponin to that eaupnd tlirereby release the interlicking member so as to permit operation of any other electromagnetically operated switch corresponding to the same floor and direction of travel.

5. An elevator signaling system for a pluralitv of cars, comprising landing signals and car operated switches corresponding with the respective cars, each car'operated switch having a plurality of contacts corresponding to the respectivelandings` and contact' means operated in correspondance with the movement of the car for connecting.

said contacts; a car signal in each car; a source of current; control circuits connected thereto and including circuit closets at the landings and corresponding clectro-magctic control means; landing signal operating cir cuits including a source of current, aud each including only one of said landing signals and also including conncctable cont-acts of the corresponding car operated switch, and a corresponding circuit closer operated by the respective electromagnetic control means, so as to be controlled by the said car operated switches and by said control circuits; car signal operating circuits having curren't suply connections and including the respective car signals, corresponding contacts of the car operated switch, and corresponding circuit closeis operated by the electro-magnetic means aforesaid, so as to he controlled hy said car operated switches and by said control circuits; and interlmzking means responsive to the operation of auf.Y landing signal operating circuit to prevent effective operation of any landing signal or cur signal circuit for another car, whilensuch first operating landing .signal clrcuit is maintained.

6. An elevator signal system as set forth in claim 5, and comprising in addition a manually operated transfer switch included in and adapted to open the operating circuits for both the landingr signals and the car signals, and thereby release the interlocking means.

7. In a multiple elevator signi-.l system, :i plurality of cars, landing;- signal means individual to each of said cars; signal operating circuits therefor; a plurality of ra r operated `circuit controllers individual to said cals and each provided with Contact means included in the circuit for the corresponding car and with moving brush means adapted to cooperate with said contact means to establish connections in said circuits; a source of current included in said circuits; each of said signal operating circuits normally including a resistance means sufliciently great to make the effective resistance of such circuit-sufhciently high to render the initial current produced therein upon such estalilishment of the circuit connection by the corresponding car-operated circuit controller ineffective for operation of the corresponding landing signal, means operated by such initial current for short-circuiting such resistance means so as to reduce the el'ective resistance of the circuit and render the current therein effective for operation of said landing signal; and interlock means operable upon operation of ,any one of said shortcircuiting means to prevent. the short-circuiting means for any of the other circuits for the same floor and direction of travel from operating.

8. In a multiple elevator signal system. a plurality o cars, car operated circuit mutrollers individual to said cans; a control circuit including a manually operated circuit closer and an electromagnetic control device; a circuit closer controlled by said electro-magnetic.control device signal op erating circuits individual to said cars and each including contacts associated with the corresponding car-operated circuit controller, and said signal operating circuits all including said` electro-magnetically controlled circuit closer in common, said circuit cnntrollers operating in conjunction with said lastnamed circuit closer to establish the cm.'- respondipg signal operating circuits; :i snnrce or current; each of said signal operating circuits being' connected to said source of current so as to produce a current in such circuit upon establishment thereof, and cach of said signal operating circuits in- NEG eluding a landing signal and normally including a resistance means sufiicient to render the initial current therein ineffective for operating said landing signal; electromagnetic means in each of said signal operating circuits; means operated by said last named electro-magnetic means upon energization thereof and adapted to short circuit said resistance means in the corresponding signal operating circuit so as to decrease the effective resist-ance of suclrcircuit and render the current therein effective for operation of the corresponding landing signal, and interlock means operable by such short circuiting means for one of said circnits'to prevent operation of the short circniting means for any' other of. said signal operating circuits.

9. An elevator signal system for a plurality of cars, comprising car signals and car-operated switches corresponding to the respective cars; control circuits inc uding a source of current, circuit. closers at the respective landings, and electromagnetic control devices; signal operating circuits including a source of current, contact means controlled by said electromagnetic controlline devices so to be operated under the control of the respective control circuits,.con tact means controlled by the corresponding car-operated switches, intercontrolling electroinagnet-ic devices associated together laccording to floors and directions of travel of the cars, and corresponding car si als; and each signal operating circuit initially including a resistance sufiicient to prevent effective operation of the correspondingY car signal; contact means controlled by' said intercontrolling electromagnetic devices and adapted to short-circuit said resistance in any signal operating circuit upon energize.- tion of the corresponding intel-controlling electromagnetic device, so as to permit. effective operation of the corresponding car signal; and interlock means operated by said intercontrolling electromagnetic devices, and adapted upon operation thereof by the intercontrolling electromagnetic device corresponding to one car to prevent effective operation of any of the other intercontrolling electromagnetic devices-associated therewith.

10. An elevator signal system as set forth in claim 9 and comprising in addition a manually ooerated transfer switch in each car adapted to open the signal operating circuit-s corresponding to that car.

11. An elevator signa-l system for a plurality of cars comprising car signals in the respective cars; a4 car operated switch corresponding to each car and having contacts corresponding to the respective fioors and directions of travel of the car and having means operated in correspondence with the movement of the car to control circuit conA nections at such contacts; signal operatinff circuits including a source of current, th respective car signals, and correspomlin 4 contacts of the car operated switches; eolitrol circuits including a source of current. circuit closers at the landings. and electro-l magnetic means; circuit closers included in thc respective signal operating circuits and operated by the respective. electromagnetic means aforesaid to close the respective signal operating circuits; cach signal ope'siting circuit also including an electro-magnel of sufiicient resistance to prevent operation of the Signal, and also including a switch cont-rolled by said elmftro-maguel` and connections including said switch and a part of said electro-magnet and adapted to short circuit said part of the electro-nmgnet to reduce the resistance of the circuit upon operation of the electromagnet, so as to cause increased current to flow in the corresponding signal operating circuit; and an interlocking member for each fioor and direction of travel, means mount-ing each of said members for cooperation with all of the electro-magnetically operated .switches for the corresponding fioor and direction of tra'vel to prevent operation of any of such: switches while any ot-her such switch for that fioor and direction of travel is in operation.

12. An elevator signal system as set forth in claim 11 and comprising in addition a. manually operated switch in each car adapted to open the signal operating circuits corresponding to that car, and thereby release the interlocking member so as to permitoperation of any other electromagnetically operated switch corresponding to the .same floor and direction of travel.

1 3. In a multiple elevator signal system. car signals in the respective cars and signal. operating circuits therefor; control circuits including manually operated circuit closer@l at the respective landings, and control electromagnet.s; means for establishing said signal operating circuit-s, comprisingswitch means operated in correspondence with the movement of the respective cars, and switch means operated by the control electro-magnets corresponding to the respective floors. means for supplying current to said signal operating circuits and said control circuits: a. resistance included in each of said signal operating circuits and suflicient to prevent effective operation of any car signal by the initial current in t-he corresponding signal operating circuit upon estahlishnient thereof, means operated by said initial current to short circnit said resistance and permit effective operation of the corresponding car signal, and interlock means operable by the short-circuiting means for any one of said llo circuits to prevent said short-circuit means for any of the other circuits for the same floor from operating.

14. An intercontrolling means for a plurality of circuits comprising, in combination With a plurality of branch conductors included in the respective circuits and with a conductor common to all of said circuits; electromagnet means individual to said circuits and each comprising a relatively low resistance portion and a relatively high resistance portion connected in series; means connecting one end of each of said electro magnet means to said common conductor, means connecting the other end of each of said electromagnet means to the corresponding branch conductor; normally open switches individual to the respective electromagnet means, the resistance of said switches being less than that of the high resistance portions of the corresponding electromagnet means and each of said switches having armature means in position to be attracted by the corresponding electromagnet means and being normally movable independently into closed position upon such attraction of said armature means; means connecting each of said switches in shunt to the high resistance portion of the corresponding electromagnetA means; and interlock means operable upon the closing of any one of said switches to prevent any other of said switches from being closed.

In testimony whereof I have hereunto subscribed my name this 14th day of August, 1923.

ROBERT H. GAYLORD. 

